What is CNC?
Computerized Numerical Control, or CNC for short, refers to the computerized numerical control of machine tools (CNC machines). Through the use of control technology, machines are able to automatically produce complex workpieces with precision, consistent high quality and in large quantities. CNC control in a machine allows you to control several axes at once, accurately and simultaneously, and allows you to perform multiple accurate cuts at a high speed.
All movements required in the production process is monitored by the CNC computer with the help of photoelectric and other sensors. This allows for complete control over the production process. Machine conditions such as oil pressure or coolant supply are also monitored, measured and controlled by the CNC computer. The control system also offers sufficient possibilities even to integrate the quality control fully automatically into the production process, therefore meaning that the use of manual labour through humans is greatly reduced with CNC machines.
Control of CNC machines
Industrial machines are usually equipped with a PLC (Programmable Logic Controller). It forms the interface between the CNC control and the plant. All fail-safe routines are carried out in the PLC. It ensures that operating modes, safety gates, coolant, lubrication, and other aggregates function. For example, it ensures that the rotating tool is switched off immediately when the safety door is opened or that the machining spindle stops automatically in the event of a collision.
The PLC is programmed once at the manufacturer and remains unchanged thereafter.
In terms of machine axis control, a distinction is made between point control (PTP control) and path control.
CNC machine language
The so-called G-code is called CNC machine language. With its help, a machine operator tells a CNC-controlled machine how to move and what to execute. The G-code consists of a line sequence of numbers and letter combinations. In the past, the G-code had to be programmed manually, but today it is generated almost exclusively by CAD/CAM programs. It is then read by the CNC software and transmitted to the CNC machines.
The CNC processes are used in industrial sectors such as metalworking, mechanical engineering, aerospace, automotive or shipbuilding.